Water is a precious resource and one of the natural elements that needs to be conserved. Many regions in the world have scare electricity production and water resources and the heavy industrial use further depletes these resources in developed and developing countries. In countries like Saudi Arabia it is critical to manage these resources and maximize the use.
Recent rural and urban development along with increase in population requires more good quality water not only for drinking but also for other uses. Electricity shortages have impeded development and effected normal life. The water shortage is becoming a global issue especially in the arid and semi-arid regions of the world. According to United Nations (1999), water shortage, besides the global warming, has been considered as the most worrying problem for the new millennium. Keeping in view this scenario, the importance of sea water desalination technology has gained momentum for the production of safe drinking water. Moreover, the conventional water desalination technologies such as reverse osmosis (RO) and others suffer from many disadvantages. These technologies are expensive to be adopted in poor countries. The RO is a pressure driven process which is highly susceptible to fouling. In addition to that, the cost effectiveness of the RO plants is strongly dependent on the energy resources such as oil and gas prices.
According to Mehta et al. (1978) pressure retarded osmosis (PRO) creates a hydraulic pressure gradient to produce pressurized brine and power may be obtained by depressurization using a hydro-turbine. Lee et al. (1981) discuss varies options to use PRO for power generation and conclude that using brine and fresh water sources and current membranes are more favorable to generate power (electricity). Loeb S (2002) describes the use of spiral membranes to produce by the application of PRO for river/sea water pair. There is a need for alternative approaches over the conventional desalination technologies and generation of power.